Macular degeneration is a clinical term that is used to describe a family of diseases that are all characterized by a progressive loss of central vision associated with abnormalities of Bruch's membrane, the choroid, the neural retina and/or the retinal pigment epithelium. These disorders include very common conditions that affect older subjects (age-related macular degeneration or AMD) as well as rarer, earlier-onset dystrophies that in some cases can be detected in the first decade of life. Other maculopathies include and dry age-related macular degeneration (dAMD), juvenile macular degenerations (JMDs) where toxic retinoids are known to accumulate as part of the pathogenesis (e.g., Stargardt disease, and Best disease), neovascular and wet age-related macular degeneration.
Age-related macular degeneration (AMD), the most prevalent macular degeneration, is associated with progressive diminution of visual acuity in the central portion of the visual field, changes in color vision, and abnormal dark adaptation and sensitivity. Two principal clinical manifestations of AMD have been described as the dry, or atrophic, form, and the wet, or exudative, form. Dry AMD is the most common form of macular degeneration and affects millions of people in the US alone. There is an ongoing and unmet need for therapies of macular degeneration.